Department of Neurosurgery, Nagasaki University Hospital, Nagasaki, Japan,
Department of Neurosurgery, Nagasaki University Hospital, Nagasaki, Japan.
Cerebrovasc Dis. 2019;48(1-2):70-76. doi: 10.1159/000503090. Epub 2019 Sep 25.
Determining the occlusion site and collateral blood flow is important in acute ischemic stroke. The purpose of the current study was to test whether arterial spin labeling (ASL) magnetic resonance imaging (MRI) could be used to identify the occlusion site and collateral perfusion, using digital subtraction angiography (DSA) as a gold standard.
Data from 521 consecutive patients who presented with acute ischemic stroke at our institution from January 2012 to September 2014 were retrospectively reviewed. Image data were included in this study if: (1) the patient presented symptoms of acute ischemic stroke; (2) MRI was performed within 24 h of symptom onset; and (3) DSA following MRI was performed (n = 32 patients). We defined proximal intra-arterial sign (IAS) on ASL as enlarged circular or linear bright hyperintense signal within the occluded artery and distal IAS as enlarged circular or linear bright hyperintense signals within arteries inside or surrounding the affected region. The presence or absence of the proximal IAS and distal IAS were assessed, along with their inter-rater agreement and consistency with the presence of occlusion site and collateral flow on DSA images.
The sensitivity and specificity for identifying occlusion site with ASL were 82.8 and 100%, respectively. Those for identifying collateral flow with ASL were 96.7 and 50%, respectively. The inter-rater reliability was excellent for proximal IAS (κ = 0.92; 95% CI 0.76-1.00) and substantial for distal IAS detection (κ = 0.78; 95% CI 0.38-1.00).
Proximal IAS and distal IAS on ASL imaging can provide important diagnostic clues for the detection of arterial occlusion sites and collateral perfusion in patients with acute ischemic stroke.
确定闭塞部位和侧支血流对于急性缺血性脑卒中至关重要。本研究旨在通过数字减影血管造影（DSA）作为金标准，验证动脉自旋标记（ASL）磁共振成像（MRI）是否可用于识别闭塞部位和侧支灌注。
回顾性分析 2012 年 1 月至 2014 年 9 月我院收治的 521 例急性缺血性脑卒中患者的资料。纳入本研究的患者需满足以下条件：（1）出现急性缺血性脑卒中症状；（2）症状发作后 24 h 内行 MRI 检查；（3）MRI 后行 DSA 检查（n = 32 例）。我们将 ASL 上的近端动脉内信号（IAS）定义为闭塞动脉内扩大的圆形或线性亮高信号，远端 IAS 定义为受影响区域内或周围动脉内扩大的圆形或线性亮高信号。评估近端 IAS 和远端 IAS 的存在情况及其与 DSA 图像上闭塞部位和侧支血流的一致性和观察者间一致性。
ASL 识别闭塞部位的敏感度和特异度分别为 82.8%和 100.0%，识别侧支血流的敏感度和特异度分别为 96.7%和 50.0%。近端 IAS 的观察者间信度极好（κ = 0.92；95%CI 0.76-1.00），远端 IAS 检测的观察者间信度较高（κ = 0.78；95%CI 0.38-1.00）。
ASL 上的近端 IAS 和远端 IAS 可为急性缺血性脑卒中患者的动脉闭塞部位和侧支灌注检测提供重要的诊断线索。
